# -*- coding: utf-8 -*- # Copyright 2019 New Vector Ltd # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. import logging import attr from twisted.internet import defer from synapse.api.constants import RelationTypes from synapse.api.errors import SynapseError from synapse.storage._base import SQLBaseStore from synapse.storage.stream import generate_pagination_where_clause from synapse.util.caches.descriptors import cached, cachedInlineCallbacks logger = logging.getLogger(__name__) @attr.s class PaginationChunk(object): """Returned by relation pagination APIs. Attributes: chunk (list): The rows returned by pagination next_batch (Any|None): Token to fetch next set of results with, if None then there are no more results. prev_batch (Any|None): Token to fetch previous set of results with, if None then there are no previous results. """ chunk = attr.ib() next_batch = attr.ib(default=None) prev_batch = attr.ib(default=None) def to_dict(self): d = {"chunk": self.chunk} if self.next_batch: d["next_batch"] = self.next_batch.to_string() if self.prev_batch: d["prev_batch"] = self.prev_batch.to_string() return d @attr.s(frozen=True, slots=True) class RelationPaginationToken(object): """Pagination token for relation pagination API. As the results are in topological order, we can use the `topological_ordering` and `stream_ordering` fields of the events at the boundaries of the chunk as pagination tokens. Attributes: topological (int): The topological ordering of the boundary event stream (int): The stream ordering of the boundary event. """ topological = attr.ib() stream = attr.ib() @staticmethod def from_string(string): try: t, s = string.split("-") return RelationPaginationToken(int(t), int(s)) except ValueError: raise SynapseError(400, "Invalid token") def to_string(self): return "%d-%d" % (self.topological, self.stream) def as_tuple(self): return attr.astuple(self) @attr.s(frozen=True, slots=True) class AggregationPaginationToken(object): """Pagination token for relation aggregation pagination API. As the results are order by count and then MAX(stream_ordering) of the aggregation groups, we can just use them as our pagination token. Attributes: count (int): The count of relations in the boundar group. stream (int): The MAX stream ordering in the boundary group. """ count = attr.ib() stream = attr.ib() @staticmethod def from_string(string): try: c, s = string.split("-") return AggregationPaginationToken(int(c), int(s)) except ValueError: raise SynapseError(400, "Invalid token") def to_string(self): return "%d-%d" % (self.count, self.stream) def as_tuple(self): return attr.astuple(self) class RelationsWorkerStore(SQLBaseStore): @cached(tree=True) def get_relations_for_event( self, event_id, relation_type=None, event_type=None, aggregation_key=None, limit=5, direction="b", from_token=None, to_token=None, ): """Get a list of relations for an event, ordered by topological ordering. Args: event_id (str): Fetch events that relate to this event ID. relation_type (str|None): Only fetch events with this relation type, if given. event_type (str|None): Only fetch events with this event type, if given. aggregation_key (str|None): Only fetch events with this aggregation key, if given. limit (int): Only fetch the most recent `limit` events. direction (str): Whether to fetch the most recent first (`"b"`) or the oldest first (`"f"`). from_token (RelationPaginationToken|None): Fetch rows from the given token, or from the start if None. to_token (RelationPaginationToken|None): Fetch rows up to the given token, or up to the end if None. Returns: Deferred[PaginationChunk]: List of event IDs that match relations requested. The rows are of the form `{"event_id": "..."}`. """ where_clause = ["relates_to_id = ?"] where_args = [event_id] if relation_type is not None: where_clause.append("relation_type = ?") where_args.append(relation_type) if event_type is not None: where_clause.append("type = ?") where_args.append(event_type) if aggregation_key: where_clause.append("aggregation_key = ?") where_args.append(aggregation_key) pagination_clause = generate_pagination_where_clause( direction=direction, column_names=("topological_ordering", "stream_ordering"), from_token=attr.astuple(from_token) if from_token else None, to_token=attr.astuple(to_token) if to_token else None, engine=self.database_engine, ) if pagination_clause: where_clause.append(pagination_clause) if direction == "b": order = "DESC" else: order = "ASC" sql = """ SELECT event_id, topological_ordering, stream_ordering FROM event_relations INNER JOIN events USING (event_id) WHERE %s ORDER BY topological_ordering %s, stream_ordering %s LIMIT ? """ % ( " AND ".join(where_clause), order, order, ) def _get_recent_references_for_event_txn(txn): txn.execute(sql, where_args + [limit + 1]) last_topo_id = None last_stream_id = None events = [] for row in txn: events.append({"event_id": row[0]}) last_topo_id = row[1] last_stream_id = row[2] next_batch = None if len(events) > limit and last_topo_id and last_stream_id: next_batch = RelationPaginationToken(last_topo_id, last_stream_id) return PaginationChunk( chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token ) return self.runInteraction( "get_recent_references_for_event", _get_recent_references_for_event_txn ) @cached(tree=True) def get_aggregation_groups_for_event( self, event_id, event_type=None, limit=5, direction="b", from_token=None, to_token=None, ): """Get a list of annotations on the event, grouped by event type and aggregation key, sorted by count. This is used e.g. to get the what and how many reactions have happend on an event. Args: event_id (str): Fetch events that relate to this event ID. event_type (str|None): Only fetch events with this event type, if given. limit (int): Only fetch the `limit` groups. direction (str): Whether to fetch the highest count first (`"b"`) or the lowest count first (`"f"`). from_token (AggregationPaginationToken|None): Fetch rows from the given token, or from the start if None. to_token (AggregationPaginationToken|None): Fetch rows up to the given token, or up to the end if None. Returns: Deferred[PaginationChunk]: List of groups of annotations that match. Each row is a dict with `type`, `key` and `count` fields. """ where_clause = ["relates_to_id = ?", "relation_type = ?"] where_args = [event_id, RelationTypes.ANNOTATION] if event_type: where_clause.append("type = ?") where_args.append(event_type) having_clause = generate_pagination_where_clause( direction=direction, column_names=("COUNT(*)", "MAX(stream_ordering)"), from_token=attr.astuple(from_token) if from_token else None, to_token=attr.astuple(to_token) if to_token else None, engine=self.database_engine, ) if direction == "b": order = "DESC" else: order = "ASC" if having_clause: having_clause = "HAVING " + having_clause else: having_clause = "" sql = """ SELECT type, aggregation_key, COUNT(DISTINCT sender), MAX(stream_ordering) FROM event_relations INNER JOIN events USING (event_id) WHERE {where_clause} GROUP BY relation_type, type, aggregation_key {having_clause} ORDER BY COUNT(*) {order}, MAX(stream_ordering) {order} LIMIT ? """.format( where_clause=" AND ".join(where_clause), order=order, having_clause=having_clause, ) def _get_aggregation_groups_for_event_txn(txn): txn.execute(sql, where_args + [limit + 1]) next_batch = None events = [] for row in txn: events.append({"type": row[0], "key": row[1], "count": row[2]}) next_batch = AggregationPaginationToken(row[2], row[3]) if len(events) <= limit: next_batch = None return PaginationChunk( chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token ) return self.runInteraction( "get_aggregation_groups_for_event", _get_aggregation_groups_for_event_txn ) @cachedInlineCallbacks() def get_applicable_edit(self, event_id): """Get the most recent edit (if any) that has happened for the given event. Correctly handles checking whether edits were allowed to happen. Args: event_id (str): The original event ID Returns: Deferred[EventBase|None]: Returns the most recent edit, if any. """ # We only allow edits for `m.room.message` events that have the same sender # and event type. We can't assert these things during regular event auth so # we have to do the checks post hoc. # Fetches latest edit that has the same type and sender as the # original, and is an `m.room.message`. sql = """ SELECT edit.event_id FROM events AS edit INNER JOIN event_relations USING (event_id) INNER JOIN events AS original ON original.event_id = relates_to_id AND edit.type = original.type AND edit.sender = original.sender WHERE relates_to_id = ? AND relation_type = ? AND edit.type = 'm.room.message' ORDER by edit.origin_server_ts DESC, edit.event_id DESC LIMIT 1 """ def _get_applicable_edit_txn(txn): txn.execute(sql, (event_id, RelationTypes.REPLACE)) row = txn.fetchone() if row: return row[0] edit_id = yield self.runInteraction( "get_applicable_edit", _get_applicable_edit_txn ) if not edit_id: return edit_event = yield self.get_event(edit_id, allow_none=True) defer.returnValue(edit_event) def has_user_annotated_event(self, parent_id, event_type, aggregation_key, sender): """Check if a user has already annotated an event with the same key (e.g. already liked an event). Args: parent_id (str): The event being annotated event_type (str): The event type of the annotation aggregation_key (str): The aggregation key of the annotation sender (str): The sender of the annotation Returns: Deferred[bool] """ sql = """ SELECT 1 FROM event_relations INNER JOIN events USING (event_id) WHERE relates_to_id = ? AND relation_type = ? AND type = ? AND sender = ? AND aggregation_key = ? LIMIT 1; """ def _get_if_user_has_annotated_event(txn): txn.execute( sql, ( parent_id, RelationTypes.ANNOTATION, event_type, sender, aggregation_key, ), ) return bool(txn.fetchone()) return self.runInteraction( "get_if_user_has_annotated_event", _get_if_user_has_annotated_event ) class RelationsStore(RelationsWorkerStore): def _handle_event_relations(self, txn, event): """Handles inserting relation data during peristence of events Args: txn event (EventBase) """ relation = event.content.get("m.relates_to") if not relation: # No relations return rel_type = relation.get("rel_type") if rel_type not in ( RelationTypes.ANNOTATION, RelationTypes.REFERENCE, RelationTypes.REPLACE, ): # Unknown relation type return parent_id = relation.get("event_id") if not parent_id: # Invalid relation return aggregation_key = relation.get("key") self._simple_insert_txn( txn, table="event_relations", values={ "event_id": event.event_id, "relates_to_id": parent_id, "relation_type": rel_type, "aggregation_key": aggregation_key, }, ) txn.call_after(self.get_relations_for_event.invalidate_many, (parent_id,)) txn.call_after( self.get_aggregation_groups_for_event.invalidate_many, (parent_id,) ) if rel_type == RelationTypes.REPLACE: txn.call_after(self.get_applicable_edit.invalidate, (parent_id,)) def _handle_redaction(self, txn, redacted_event_id): """Handles receiving a redaction and checking whether we need to remove any redacted relations from the database. Args: txn redacted_event_id (str): The event that was redacted. """ self._simple_delete_txn( txn, table="event_relations", keyvalues={"event_id": redacted_event_id} )